Black Death

The Black Death was one of the most devastating epidemics in recorded history. It reached Europe in 1347 and spread rapidly in the following years, causing enormous loss of life. The disease was caused by the bacterium Yersinia pestis, confirmed in human remains from the epidemic. The bacterium could circulate among rodents and reach people through infected fleas.

In some cases, plague could also spread from person to person through respiratory droplets, especially in pneumonic plague. Its impact varied from one region to another. Historians generally estimate that about 30 to 50 percent of Europe’s population died, although the exact death toll remains uncertain.

The plague appeared in a world shaped by war, expanding trade, population growth, and limited medical knowledge. It probably entered Europe through routes linking the Black Sea to Mediterranean ports, then moved inland with people and goods. Cities were particularly vulnerable because of their dense populations and commercial connections.

Without knowing the cause, people sought explanations in religion, medicine, or contemporary beliefs. After the major waves of the fourteenth century, plague continued to return for centuries. The Black Death changed European society, affecting work, landholding, and religious life.